An enhanced Cumulative Impact Assessment framework supporting Ecosystem-based Coastal Spatial Planning and Blue...

Ecosystem-based Coastal Spatial Planning (EB-CSP) addresses the substantial need for assessing the cumulative impacts of coastal human footprint on ecosystem services. This study proposes a holistic Cumulative Impact Assessment (CIA) methodology, leveraging open-source and modelled geospatial data, exemplified in the data-limited coastal zone of Heraklion Prefecture. The methodology assesses the impacts of land- and sea-based anthropogenic activities on Final Ecosystem Services (FES) as assessment endpoints and explores the spatial variations in CIA results engaging spatial autocorrelation and hotspot analysis. Thus, Geodetector analysis was conducted to investigate the spatial differentiation and driving mechanisms of CIA distribution, still unknown in marine regions. Results revealed that shipping and fishing activities contributed to the higher CIA values, with P. oceanica meadows being the most impacted FES. Impact hotspots were concentrated near urban centres, reflecting regional differentiation. Factor detection identified land-based activities as driving forces impacting the study area and in the northern part separately, while bathing waters dominated in the south. Among ecological influencing factors, Photosynthetically Active Radiation (PAR) was highlighted at the study area level, whereas P. oceanica was predominant regionally. Synergistic interactions prevailed between land-based activities and PAR in the study area overall, between spawning areas with urbanization and tourism in the north and bathing waters with agriculture and urbanization in the south. The proposed methodology facilitates the identification of priority conservation zones and informs decision-making for managing driving human activities in the EB-CSP context while offering actionable recommendations for future impact mitigation and sustainable ecosystem services utilization in data-limited coastal regions.